Liquid distributing system



Oct. 14, 1952 F. J. wn-:GAND Erm. 2,513,687

LIQUID DISTRIBUTING SYSTEM Original Filed Feb. 23, 194? ATTEFQNEYPatented Oct. 14, Q

UNITED STATES PATENT oEFicE LIQUID DISTEIBUTING SYSTEM Francis J.Wiegand, Ridgewood, William T. Stark,

Pompton Lakes, and Mark VR'. Rowe, Teaneck, Y N. J., assignors toCurtiss-Wright Corporation, a corporation of Delaware Originalapplication' February 23, 1944, Serial No.

523,770, now Patent No. 2,430,264, dated No vemberV 4,` 1947. Dividedand this application ctober 17,41947, Serial No. 778,418

cally maintains said equal division 'of' ow' be-l tween the plurality ofpassages notl lonlyiwith changes in the total magnitudeof the flow butalso with changes in the relative elevation of said passages.

The invention is described in connection with a fuel distributing systemfor amulti-,cylinder internal combustion engine. As will appear,however, the invention herein claimed is not so limited and insteadisofgeneral application.

Other objects of the invention will become apparent upon reading the.annexed detailedv de", scription in connection with the drawing in Lwhich:

Figures 1 and 2 are schematic rear end and side views, respectively,illustrating the invention applied to a radial cylinder internalcombustion enginaand l Figure 3 is a detailed section View 'ofone of thedischarge nozzles.

Referring to the drawing, a conventional radial cylinder aircraft engineI0 is provided with radially disposed cylinders II having intake andexhaust valves l2 and I3, respectively.' 'A carburetor or other fuelmetering device I4, to which fuel is supplied under pressure, issupported on the engine or section I6. LA carburetor adapter or conduitsection I8 establishes communication between the carburetor and theintake of a conventional engine driven super'- charger 26, which in turndischarges the com` bustion air into an annular manifold 22 from whenceit is distributed to the various engine cylinders through theirintake'pipes 24.v The structure so far describedisv quite conventional.`

The fuel metering device Himay comprise any suitable mechanism to whichfuelis' supplied under pressure and in which the fuel is metered anddelivered under pressure, for example, in accordance withthe total airflow as in the fuel metering device disclosed in Patent No. 2,165,447 toK. Browne. The metered fuel is deliveredto a fuel reservoir or fueldistributing manifold 26 which, as illustrated, comprises twosemi-circular branches disposed about the bases of the radially disposedcylinders il.v Each of the intake pipes 2liA is provided withafuelvdischarge Valve 0r nozzle 28 having its inlet "sideconnected tothe fuel distributing manifold through la conduit 36. The fuelpressure-communicated from the manifold 26 through conduits 3i! to eachdischarge Valve, urges each valve in an opening direction against asuitable spring or other balancing force. If the engine were always toremain in a substantially constant attitude, the spring biasing forcefor urging each of the valves in a clos-` ing direction could beadjusted to, compensate for the difference in fuel pressure at eachvalve resulting from `their difference in elevation. That is, with theengine remaining in a substantially constant attitude each valve 23 maybe adjusted such that fuel is always discharged at the same rate intoeach of the intake pipes 24. Upon an increase or a decrease in theamountof fuel supplied to the manifold 26, each valve 23 will open or close todischarge fuel at a corresponding larger or smaller rate into .therasso` ciated intake pipe.

With such an arrangement and with the en,- gine maintained in aconstantattitude, fuel is continuously discharged into each of the`intake pipes at equal rates, the fuel ,being picked upv by the airsupply to each intake pipe and taken into the associated cylinders ontheir intake strokes. However, `in operation, particularlyin an aircraftengine installation, the relative yele"- vation of thevarious fueldischarge valveswill be continuously changing, and therefore, it ,is

essential that such changes in relativeelevation of the various valveshave no effector have the same effect on each valve in order to maintainthe proper division of fuel flow through the valves. i

To this end each fuel valve and the entire fuel system is designed sothat fuel is admittedtol both sides of the valve operating means insuch.l

a manner that the differential fuel pressure a'ct ing on each valveoperating means is theI same.-

regardless of the relative elevation ofi-these valves. With such asystem the fuel discharge valves may be adjusted to properly divide 'thefuel flow regardless of the attitude ofthe engine..

Referring particularly to FigureB, each valve" 28 comprises a housing oftwo halves 32 and 34. between which a diaphragm 36 is supported. ,Aymovable valve member 38 is secured to thediaphragm 36 by a nut 46 and isslidablyreeeived within an annular valve guide 42.

periphery. The housing part 32.. has an inlet" opening 50 for theconduit3U, whereby fuel isfadgmitted therefrom to the interior of thehousingand against the valve side of the diaphragm 36.

The valve'. guide 42 is threaded within the housing part 32 The annularvalve. guide 42 is provided with one or more circumferentially spacedopenings 52 and the valve member has a tapered end 54 cooperatingtherewith. For clarity this taper has been greatly magnified in thedrawing. With this construction upon axial movement of the valve member38, the junction 55 of its tapered end 54 with the remainder of thevalve member moves across the openings 52 to control the extent to whichthe valve is open.

The valve housing part 34 is provided with an adjusting sleeve 56threaded therein and an axially disposed adjusting screw 58 is threadedthrough one end of said sleeve. The screw 58 is provided with a head end6B having a helical groove 62 about its periphery for receiving one endof a helically coiled spring 64. The other end of the spring 64 engagesthe nut 4I) to urge the valve member 38 in a closing direction againstthe fuel pressure acting on the valve side of the diaphragm 36. Upon anincrease in the fuel supplied to the fuel manifold 26, there will be` anincrease in the fuel pressure therein and at the inlet side of each ofthe valves, whereby this increased fuel pressure acts against the valveside of each valve operating diaphragm 36 to effect a further'opening ateach of the valves to maintain a proper division of the fuel flow. Anyadjustment of the screw 58 relative to the sleeve 56 threads thevhelical groove. 6.2 of the head 60 along the spring, thereby controllingthe length and stiffness of the spring. Also, adjustment of the sleeve56 deter-mines the fuel pressure at which the valve member 38 begins t0open. In order that the sleeve 5.6 may be adjusted without disturbingthe adjustment of the spring B4, the threads on the exterior of theadjusting sleeve 56 may be right handed and its internal threadscooperating with the screw 58 may be left handed, but of the same pitch.A lock nut 66 and a cap 68 are threaded about thesleeve 56 asillustrated.

In addition to the action of the springs 64,each of the valves 38 isalso urged in a closing direc tion by a fuel pressure admitted to thehousing portion 341 and against the rear side of the diaphragm 36.through an inlet opening lil- The housing portion of each valve 34 isalsoprovided with an outlet opening l2, and conduits 14 interconnect theexit opening l2 of one valve housing with the inlet opening of anothervalve housing to serially connect. the chambers at the rear sides of thediaphragms 36. As illustrated in Figure 1, the housing partsl 34 of thefuel discharge valves for cylinders on the one side of the engine areserially connected together, and similarly, the valve housing parts 34associated with the cylinders on the other side ofv the engineareserially connected together. Also, the lower ends of' the fuelmanifold'- 26 4are connected to the inletv openings of the valve housingportions 34 for the lower end cylinders of each series throughrestricted orifices 1562 and conduits '18. The outlet openings 'I2 ofthe valvey housing portions 34; for the upper end cylindersofeachfseriesare connected through conduits 8U toa valve 82l dischargingy into thecarburetor adapter.v The valve 82 is a commonvtype valve which isAspring biased toward closed position and is urged toward open. positionin response to the fuel pressure supplied thereto. The valve S2 isdesigned to maintain a small back pressure in order to insure that theconduits 14, 1:8 and 86 and housings 34 remain full of fuel. Because lofthe small size of the restricted orifices 16, the magnitude and therange ofA thebackl pressure maintained by the valve 82 is much smallerthan the magnitude and the range of the fuel pressure within themanifold 26. For example, the fuel discharge pressure at each dischargevalve may vary from nine to eleven pounds per square inch between theirclosed and full open positions, While the back pressure maintained bythe valve 82 varies from one to two pounds per square inch. The orices16 are designed such that the flow through the valve 82 is quite small;for example, a fuel flow through the valve 82 amounting to but onepercent of the total fuel flow has been found to be satisfactory.

With this system each valve assumes a position in which the fuelpressure on the valve side of the diaphragm 36 balances the force of thespring 64 and the fuel pressure on the other side ofv the. diaphragm.Upon an increase or a decrease in the amount of fuel supplied te thefuel distributing manifold 26 there will be. a simi'- lar opening' orclosing adjustmenty of each fuel discharge valve to maintain a properdivision of fuel flow. Also, the fuel pressure on the valve side of anytwo diaphragms 36' differs only by an amount dependent. on thedifference inthe fuel head. at each diaphragm, which depends only on thedifference in. elevation. of. the two diaphragms. Similarlyr thedifference in the fuer pressure on the rear side of any two. diaphragmsdiffers only byA an. amount dependent-ori the dif.- ference in the fuelhead at' eachl diaphragm, which differencev also depends only on .thedif'- ference in elevation of the two diaphragme. That is, if. any onediaphragm. 36 is at a higher elevation than a second' diaphragm, thefu'eli pressure 0n both sides of the. one vdiaphragm will be greaterthan the corresponding fuel? pressures oni the two sides' ofv the:second diaphragm. by amount equal to the. pressure resulting fromy afuel head corresponding to their difference in elevation. Inother'words, the: fuel pressure dif. ferential on each diaphragm 36 isthe same ree gardless of' their relative elevation andi therefore theextent to which'. eachvalve opening 5261s' uncovered is always :the:same and the fuel flow through each valve is substantially the: same.Actually, although each valve opening 52 is uncovered to the sameextent, the pressure diiferential across these openings. will. .beslightlyy larger for thev lowerva'lves because of the' larger staticfuel. hea-eL on: their inlet sid'es. However, this latter` variation.in. pressure differential has substantially no effect on therelativemagnitudel of the fuel ow'through each valve, particularly r as comparedto` the: effect on fuel flow which a corresponding variation'. inpressure differential across the diaphragrnsl 361 would have becauseofthe resulting variation in the extent towhicheach valve opening 5'2wouldbeuncovered. Infact, each valve 281 obviously maybe so designedthat the fuel pressure differential between` its inlet andoutlet'sidesissuchat each' valvel open-y ing that the flow vthrough thevalve-depends primarily only on theI extent to which the valve opening52 is uncovered,

While we have described our inventionV in den tail in its presentpreferred embodiment, it will be obviousto those skilled in the art,after derstanding our invention, that various changes and modificationsmay be made thereinwitliout thev spirit or scope thereof, We aim 1n theappended claims to cover all such modifications and changes'.

We claim as 'our invention:

1. A fluiddistributing system-'comprising a plurality of valve housings,each of said housings having a movable member dividing said housing intofirst and second chambers, each of said housings also having a fluiddischarge opening communicating with said first chamber and having avalve connected to the associated movable member for controlling theassociated discharge opening; a fluid manifold; first passage-- waysconnecting said manifold with each of said first chambers; means forsupplying a fluid under pressure to said manifold for distributiontherefrom through said passageways, through the first chambers andthence through the discharge openings of said chambers, the fluidpressure in each of said first chambers urging the associated movablemember in a direction for opening its valve; means providing a source offluid pressure less than the pressure of the fluid supplied to saidmanifold; and second passage- Ways connecting said source of fluidpressure with each of said second chambers, the fluid pressure in eachof said second chambers urging the associated movable member in adirection for closing its valve.

2. A fluid distributing system comprising a plurality of valve housings,each of said housings having a movable ,member dividing said housinginto rst and second chambers, each of said housings also having a fluiddischarge opening communicating with its first chamber and having avalve connected to its associated movable member for controlling itsassociated discharge opening; a fluid manifold; first passagewaysconnecting said manifold with each of said first chambers; means forsupplying a fluid under pressure to said manifold for distributiontherefrom simultaneously through said passageways and thence throughtheir respective first chambers and the discharge openings of said firstchambers, the fluid pressure in each of said first chambers urging theassociated movable member in a direction for opening its valve; meansproviding a source of fluid pressure less than the pressure of the fluidsupplied to said first manifold; and interconnected passagewaysconnecting said source of lesser fluid pressure with each of said secondchambers, the fluid pressure in each of said second chambers urging itsassociated movable member in a direction for closing its valve.

3. A fluid distributing system comprising a plurality of valve housings,each of said housings having a movable member dividing said housing intofirst and second chambers, each of said housings also having a dischargeopening communicating with its first chamber; a uid manifold; firstpassageways connecting said manifold with each of said first chambers;means for supplying a fluid under pressure to said manifold fordistribution therefrom simultaneously through said passageways andthence through their respective first chambers and the dischargeopenings of said first chambers; means providing a source of fluidpressure less than the pressure of the fluid supplied to said firstmanifold; second passageways for continuously connecting said source oflesser fluid pressure with each of said second chambers during operationof said system; and a valve connected to each of said movable membersfor controlling its associated discharge opening for providing equalsimultaneous rates of fluid discharge through said discharge openings,each of said movable members being urged in a direction for opening itsvalve by the fluid pressure in its first chamber and being urged in theopposite direction by the fluid pressure in its second chamber.

4. A fluid distributing system as recited in claim 3 and includingsprings for urging each of said movable members in a valve closingdirection.

5. A fluid distributing system comprising a plurality of valve housings,each of said housings having a movable member dividing said housing intofirst and second chambers and providing an imperforate wall between saidchambers, each of said housings also having a discharge openingcommunicating with its first chamber; a fluid manifold; open passagewaysconnecting said manifold with each of said first chambers; means forsupplying a fluid under pressure to said manifold for distributiontherefrom simultaneously through said passageways and thence throughtheir respective first chambers and the discharge openings of said firstchambers; means providing a source of fluid pressure less than thepressure of the fluid supplied to said first manifold; secondpassageways for continuously connecting said source of lesser fiuidpressure with each of said second chambers during operation of saidsystem; and a valve connected to each of said movable membersforcontrolling its associated discharge opening for providing equalsimultaneous rates of fluid discharge through said discharge openings,each of said movable members being urged in a direction for opening itsvalve by the fluid pressure in its first chamber and being urged in theopposite direction by the uid pressure in its second chamber.

6. A fluid distributing system comprising a plurality of valve housings,each of said housings having a movable member dividing said housing intofirst and second chambers, each 0f said housings also having a fluiddischarge opening communicating with said first chamber and having avalve connected to its associated movable member for controlling itsassociated discharge opening; a fluid manifold; first passagewaysconnecting said manifold with each of said first chambers; means forsupplying a fluid under pressure to said manifold for distributiontherefrom simultaneously through said passageways and thence throughtheir respective first chambers and the discharge openings of said firstchambers, the fluid pressure in each of said firstv chambers urging theassociated movable member in a direction for opening its valve; meansproviding a source of fluid pressure less than the pressure of the fluidsupplied to said first manifold; and passageways serially connectingsaid second chambers to said source of lesser fluid pressure for fluidflow through said second chambers, the fluid pressure in each of saidsecond chambers urging its associated movable member in a direction forclosing its valve.

FRANCIS J. WIEGAND.

WILLIAM T. STARK.

MARK R. ROWE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number

